Machine Learning Model for Lithographic Mask Pattern Generation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current lithographic technologies face challenges in accurately reproducing small feature sizes and high feature densities due to limitations in resolution enhancement techniques, leading to sub-optimal performance and increased errors in patterning processes.

Innovation Solution

A machine learning model is trained to generate characteristic patterns for mask patterns using a continuous transmission mask (CTM) and reference patterns, reducing metrics between the generated patterns and the CTM and reference patterns, thereby improving patterning process performance and manufacturability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional resolution enhancement techniques are used, then lithographic patterning can be performed, but manufacturing precision deteriorates due to inability to accurately reproduce small feature sizes and high feature densities

Engineering Contradiction:
Improveaccuracy of reproducing small feature sizesVSAvoidpatterning process performance
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent replaces conventional mechanical/optical resolution enhancement techniques with a machine learning-based computational system. The ML model processes CTM data to generate characteristic patterns, substituting physical resolution enhancement methods with an intelligent algorithmic approach that can accurately reproduce small features and high-density patterns without the limitations of traditional optical systems.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent transforms the continuous transmission mask (CTM) data through a machine learning model that learns optimal parameter transformations. The model adjusts pattern parameters such as feature sizes, spacing, and densities to generate characteristic patterns that meet manufacturing requirements, effectively changing the parameter space from raw CTM data to manufacturable mask patterns.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If conventional patterning methods are used, then manufacturing can proceed, but errors increase leading to sub-optimal performance

Engineering Contradiction:
Improvepatterning process performanceVSAvoidpattern accuracy
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent implements a feedback mechanism where the machine learning model is trained using reference characteristic patterns and CTM data. The model learns from the relationship between input CTM patterns and desired output characteristic patterns, continuously improving its accuracy. This feedback loop enables the system to reduce patterning errors and achieve optimal performance by adjusting its internal parameters based on training data.

Inventive Principle:
Principle #23Feedback

3Productivity

If traditional mask pattern generation is used, then manufacturing can continue, but critical dimension uniformity and yield are reduced

Engineering Contradiction:
ImproveyieldVSAvoidcritical dimension uniformity
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent performs preliminary pattern generation and optimization using the machine learning model before actual mask manufacturing. The model generates characteristic patterns that are pre-optimized for manufacturability, critical dimension uniformity, and yield. This preliminary computational action allows potential issues to be identified and corrected before physical manufacturing, improving both productivity and precision.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentUS20220335333A1Methods for generating characteristic pattern and training machine learning model
Publication Date: 2022.10.20 ASML NETHERLANDS BV
  • US20220335333A1 patent drawing
  • US20220335333A1 patent drawing
  • US20220335333A1 patent drawing

AI summary

Methods of generating a characteristic pattern for a patterning process and training a machine learning model. A method of training a machine learning model configured to generate a characteristic pattern for a mask pattern includes obtaining (i) a reference characteristic pattern that meets a satisfactory threshold related to manufacturing of the mask pattern, and (ii) a continuous transmission mask (CTM) for use in generating the mask pattern; and training, based on the reference characteristic pattern and the CTM, the machine learning model such that a first metric between the characteristic pattern and the CTM, and a second metric between the characteristic pattern and the reference characteristic pattern is reduced.